What are spring tides and neap tides?

Springs and neaps

What are spring tides and neap tides? and lower than average low tides. These are called spring tides. When the Earth, Moon and Sun form a right angle (at 90°) the high water caused by the lunar tide coincides with the low water of the solar tide. This produces lower than average high waters and higher than average low waters which are called neap tides. They occur approximately 7 days after spring tides.